1. Field of the Invention
The present invention relates to a mobile communication terminal including a Radio Frequency Identification (RFID) reader and a transception method thereof More specifically, the present invention relates to a mobile communication terminal including an RFID reader having a shared antenna for RFID transception and wireless telecommunications transception.
2. Discussion of the Background
Today's mobile communication terminal may perform many various functions, such as wirelessly connecting to the internet, video conferencing, text messaging, and video messaging, in addition to voice communication as information communication technologies continue to develop.
As the digital age continues to mature, mobile communication terminals have developed into high-speed digital information terminals capable of transmitting a high quantity of data at a very high speed. Thus, efforts have been made to form one network over which the terminals may operate. For this network, technologies including wireless local area networks (LANs), Bluetooth, and RFID have been used.
RFID is one technology in the field of automatic recognition technology, which includes bar codes, magnetic sensors and IC-cards or “Smart” cards. RFID includes technology whereby data or information stored in a microchip on an RIFID tag may be read or recognized wirelessly by an RFID reader using RF waves, which may be for example high frequency (HF), very high frequency (VHF), or ultra high frequency (UHF) waves. The RFID tag may be passive, whereby the RFID tag has no independent source of power. These passive RFID tags may draw sufficient power to transmit a signal representing the data stored in the microchip from the RF waves transmitted from the RFID reader. Alternatively, the RFID tag may be active, whereby the RFID tag may include its own source of power for transmitting data to the RFID reader. The RFID tag may be a transponder. Accordingly, upon receiving an RFID signal from the RFID reader, the RFID tag may automatically transmit a signal representing data or information, or a signal including data or information stored in the microchip.
Currently, RFID technology has been widely used in industries instead of the bar code. One advantage of the RFID is that the RFID tag may transmit data stored in the microchip without needing to contact a reader directly or without needing to be visibly scanned by the reader. Rather, the RFID tag may be in the proximity of the reader to transmit the data. The proximity of the RFID tag and RFID reader for successful transmission of data may depend on an operating frequency of the RFID tag and RFID reader. For example, an RFID tag and RFID reader operating in a HF range may be able to transmit data within a range of approximately one meter of the RFID reader.
RFID technology has become popular over internet and LAN technology as a type of automatic recognition technology because the RFID reader and RFID tag may operate outside of a range of a wireless connection to the internet or to an LAN.
As a result of the advantages of the RFID technology, a mobile communication terminal with a built-in RFID reader as described above has been developed.
FIG. 1 shows a block diagram illustrating a conventional mobile communication terminal with a built-in RFID reader. While the conventional mobile communication terminal shown in FIG. 1 will be described as a Global System for Mobile Communication(GSM)-based mobile communication terminal, mobile communication terminals operating according to other wireless protocols, such as Code Divisional Multiple Access (CDMA) or Wideband CDMA (WCDMA), may be similarly arranged.
The conventional mobile communication terminal with a built-in RFID reader may include a GSM base band unit 10, a GSM RF unit 20 controlled by the GSM base band unit 10 for performing transception of voice communication, and an RFID unit 30 with a built-in RFID reader for transception of RFID-based signals. Transception shall mean both transmission and reception of signals, such as voice signals, information signals, data signals, or RFID signals, and shall not be spatially limited to only transmission or only reception at an instant of time.
The GSM RF unit 20 may include an RF transception unit 21, a clock generating unit 22, a filter 23, a high output amplifier unit 24 with a first power amplifier PA1 and a second power amplifier PA2, an antenna switch module 25 and an antenna 26. The RFID unit 30 may include an RFID reader control unit 40, an RFID RF unit 50 and antenna 80.
More specifically, the RFID RF unit 50 may include an RFID transception unit 60, a switch SW1 and an RFID reception unit 70. The switch SW1 may have two positions and may allow the RFID transception unit 60 to transmit a transmission signal from the antenna 80 while the switch SW1 is in a first position, and may allow the RFID reception unit 70 to receive a reception signal at the antenna 80 when the switch SW1 is in a second position. The RFID transception unit 60 may include a modulator 61, a first amplifier AMP1, a second amplifier AMP2, a third power amplifier PA3, a first filter F1, a second filter F2, a power division unit 62 and an attenuation unit 63. The RFID reception unit 70 may include a demodulator 71, a power division unit 72, a low noise amplifier LNA1 and a third filter F3.
The demodulator 71 may include mixer M1 and mixer M2, amplifier AMP3 and amplifier AMP4, filter F4 and filter F5, and amplifier AMP5 and amplifier AMP6. The mixer M1 and mixer M2 may each demodulate a power-divided signal of the power division unit 72 and downconvert the frequency of the power-divided signals. The amplifier AMP3 and amplifier AMP4 may amplify output signals of the mixer M1 and the mixer M2, respectively. The filter F4 and filter F5 may filter output signals of the amplifier AMP3 and amplifier AMP4, respectively. The amplifier AMP5 and amplifier AMP6 may amplify output signals of the filter F4 and filter F5, respectively. The output signals of amplifier AMP5 and amplifier AMP6 may be output to RFID reader control unit 40.
The modulator 61 may modulate a transmission signal and regulate its frequency upward, and the demodulator 71 may demodulate a reception signal and regulate its frequency downward. The transmission signal and the reception signal may each correspond to an operating frequency of the RFID, which may be 13.56 MHz.
The above-described mobile communication terminal with a built-in RFID reader may control the GSM RF unit 20 and the RFID RF unit 50 separately through the GSM base band unit 10. As a result, a circuit may be complicated, thus increasing the manufacturing cost, and the circuit may occupy a large area in the mobile communication terminal. Thus, the size requirements of the circuit may prevent the terminal from being sized smaller according to the prevailing trend in terminal sizes.
Moreover, the RFID unit 30 may not operate properly and may not be recognized when separated from the reader by a distance greater than one meter because the RFID may be configured to operate at an HF frequency, such as 13.56 MHz, which is lower than an operating frequency of the GSM RF Unit 20 since the GSM RF Unit 20 may operate in the UHF band.